This invention relates generally to a solar furnace and more specifically to a liquid heating solar furnace which is self-pumping by means of a vapor generator pump.
While there exist, both in the literature and commercially, solar heat collection systems which do not require external power to pump the heat transfer fluid to a hot water tank or heat exchanger, such systems depend on natural convection currents and differing elevations, and are thereby limited in the distance and particularly in the height they can move the heated liquid.
The typical residential structure requires a lift of the heat transfer liquid of at least ten feet, and, for a two-story house with attic, requires approximately twenty-five feet. Such heights make convection flow impractical and invariably lead to the use of electric pumps for liquid movement. Not only is this philosophically distasteful to most persons who are interested in the use of solar energy, but it limits the use of solar heating to locations where electrical power is available, and thereby is counterproductive to solar energy's greatest benefit, independence from commercial power sources.
It is therefore the object of this invention to furnish a heater for liquids which is powered only by solar energy and which requires no outside source of power for pumping the liquid.
A further object of the present invention is to supply a solar heating system which has independent solar collectors for heating and for pumping the heat transfer fluid.
A still further object is to yield a solar heating system which, not only pumps liquid without auxilliary sources, but is also capable of circulating heated water throughout all areas, including the upper floors, of a residence.
A further object of the invention is to permit optimum location of the solar pumping collector and vapor generator pump, and, through the use of a heat pipe, eliminate the requirement that they be in close proximity.
A still further object is to furnish a solar heating system with simple controls which operate without external power sources, and which maintain required water temperature but prevent overheating.